FLOOD00872

• County: Boulder
• Community: Longmont, Boulder County
• Stream Name: Lefthand Creek
• Title: Floodplain Information Report
• Date: 12/1/1981
• Prepared For: Boulder County
• Prepared By: UDFCD
• Contract/PO #: &&
• Floodplain - Doc Type: Floodplain Report/Masterplan

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TABLE 7
FLOOD FREQUENCY-ELEVATION AND DISCHARGE DATA
Lefthand Creek Boulder County, Colorado
Distance StreaJi. 10-Year 50- Year 100-Year 500-Year
Reference From Bed Flood Peak 2 Flood Peak 2 Flood Peak 2 Flood Peak 2
Point Mouth Elevation Elevation Discharge--L Elevation Discharge--L Elevation Discharge--L Elevation Discharge ...i..
Nwnber Ft. Identification Ft, -m, s.1. Ft.-m,s.1. c, f.s. Ft. -m. s, 1. c.f.s, Ft.-m,s.!. c, f, s. Ft,-m.s.1. c.f.s.
0+00 Mouth 4915.2
4 4+50 4918.8 4922.9 520 4926.5 2480 4927.3 4610 4928.0 10320
5 8+10 4919,7 4924.0 4928.0 4928.6 4929.5
5.1 9+00 4920.7 4924.2 4928.0 4928.7 4930.2
5.2 9+10 Diversion Structure 4925.0 d/s 4924.2 d/s 4928.0 d/s 4928.7 d/s 4930.2
u/s 4927.3 u/s 4930,3 u/s 4930.7 u/s 4931.2
5,3 9+20 4922,9 4927,3 4930,3 4930.7 4931. 2
6 12+90 4924.8 4928.4 4931.4 4931. 8 4932.5
6.1 20+25 4929.3 4932,4 4935.9 4936.3 4936,9
7 20+75 Private Drive 4929,5 d/s 4932.4 d/s 4935,9 d/s 4936.3 d/s 4936,9
u/s 4936.0 u/s 4936.7 u/s 4937.1 u/s 4937,8
8 21+00 4929.8 4936,0 4936.7 4937.1 4937,8
9 25+90 4930.8 4936.3 4937.9 4939.0 4939,5
10 33+40 4931,8 4937.6 4941. 0 4941.6 4942,5
11 37+10 4933.1 4938,4 4941.8 4942.6 4943.4
12 45+40 4936.4 4940,7 4944.4 4945,7 4948,0
13 52+90 4939.0 4943.5 4947.7 4950,7 4952.9
14 55+00 North 107th Street 4939.5 d/s 4943.5 d/s 4947,7 d/s 4950.7 d/s 4952.9
u/s 4945,3 u/s 4949,7 u/s 4952.1 u/s 4955.6
1/ Low water elevation as determined by aerial photogrammetric methods,
2/ Discharges are prorated between stations.

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